1. Technical Field
The invention relates to lower internals for nuclear reactors; it is particularly suitable for use in pressurized water nuclear reactors (PWRs).
However, the invention is also applicable to other types of reactors, particularly those of the type comprising a vessel withstanding the pressure of a coolant; a core formed of upstanding fuel assemblies carried by a lower support plate formed with passages for the upward flow of coolant; separation means defining a volume located between the support plate and a lower portion of the vessel, said separation means having a wall and ducts for conveying coolant to said passages through the wall and the volume; and guide tubes passing through the volume for guiding glove fingers for in-core instrumentation probes.
2. Prior Art
Different lower internals for nuclear reactors are already known. U.S. Pat. No. 4,842,813 describes lower internals of the above-described type. In such internals, the distribution of the guide tubes for the instrumentation probe "glove fingers" in the volume placed in the lower portion of the reactor vessel is complex when the number of coolant conveying ducts is high.